Roll stand



2 Sheets-Shet l /'kf alN ENTOR ROLL STAND H. C. INSLEE Filed May 15,1942 ATTORNEY I L F I Patented Sept. 26, 1944 UNITED STAT-as PATENTOFFICE mesne assignments, to Rockrlte Processes, Inc., I Stamford,Conn., a corporation of Delaware Application May 13,

17 Claims.

This invention relates to roll stands for rolling -mills, and moreespecially to an improved duplex two-high roll stand. ,The invention hasbeen made especially with the idea of providing a roll stand for a ne'iiduplex step-by-step reducing mill of the pilger type for which I havefiled an application for patent Serial No. 442,769, filed May 13, 1942;but roll stands according to the invention may be used in other millsfor rolling tubes or solid bars or rods.

, The invention aims to provide an I, improved roll stand, and moreespecially a duplex roll stand, that is, one having two pairs of workingrolls, inwhich the rolls shall be readily accessible for removal andreplacement and during operation, in which the rolls shall be so mountedand supported as to be capable of resisting very great spreadingpressures in use with a minimum of displacement, and which as awholeshall be of great strength and'rigidity;

A roll stand accordingj'totheinvention and embodying all. features ofthe invention in the preferred form comprises a-housing in the form of amassive frame having a through opening, or

window, two pairs of overhung working rolls atopposite sides of thehousing fast on opposite ends of two shafts mounted in bearings inblocks ad justably held in the window of the housing, and upper andlower overhung backing, or back-up, rolls for each pair of workingrolls, the backing rolls being mounted to rotate "on fixed axlesextending from blocks adjustably, held in the win-- dow of the housing,and the bearings for the backing rolls being spherically curved bearingswhich permit the backing rolls to adjust themselves to bear evenly onthe working rolls in spite of any possible deflection which may occur.

the\blocks which carry the backingrollsghereby to force thebaclringollsagainst the working,

sure on the workpiece inactual reducing, that is, the preload on eachpair of working rolls is approximately equal to the rolling load on eachpair of these rolls. By such preloading, the yield under load is reducedto a minimum," and there is practically no change of stress in the millparts when a tube or other workpiece is entered, so

that the shape and dimensions of the roll passesqii therollsaresetiupwith a 1942, Serial No. 442,768

will be maintained whether tubes are being reduced in oneor both of theroll passes, and the mill will deliver almost exactly the same sizetubes whether one or two tubes are in the rolls. Other novel features ofthe new roll stand, including means'for certain necessary adjustments,will appear from the following description in connection with thedrawings. While, as stated, theinvention aims especially to provide aduplex roll stand, that is, one having two pairs of die rolls, or otherworking rolls, one

pair on each side of the housing, yet, since, as

pointed out above, the shape and dimensions of the roll passes will bemaintained whether tubes or other workpieces are being reduced in one orboth of the roll passes, the roll stand is adapted foruse'with only onpair of working rolls, the corresponding pair of rollson the other sideof the housing being thennot working rolls but merely coacting rollswhich may have plane surfacesand which serve to maintain the stress in"the mill parts in balance. Theroll stand is thus adaptable for use in asingle mill as well asin a. duplex mill. w 2 A 'A full understanding ofthe inventioncan best be given by a detailed description of a roll standembodying the various features of the invention in the form nowconsidered best, and such a deg c and Means are provided for applyingpressure to Fighiis a detail section-taken on line 55 of 4 Fig.1. Q

Referring to the drawings, the roll stand com prises a housing, orframe, In? and two pairs of ov'erhung circumferentially grooved working,or die;;-rolls II and I2, and an overhung-backing roll l {Ior-eachmpperdie roll, and aiigvrhung back ing rolH-kforeach lower mean. The housingv| I] -is of massive construction, most desirably and as shown, a metalcasting, in the form of an upright rectangular frame having a throughopening, or window. The twopairs of die rolls are mounted 1 at oppositesides of the housing fast on shafts l5 and I6 which are rotatablymounted and held against endwise movement in blocks l1 and I8 adjustablyheld in the window'of the housing. The upper backing rolls H] arerotatably mounted always hear evenly on weight.

The backing rolls are mounted on their dead axles by means ofspherically curved bearings 25 which permit the rolls to adjustthemselves to the working rolls on which they bear so that they willalways bear evenly on their respective working rolls in spite of anypossible deflection which may occur. Most desirably, these backing rollbearings are spherical roller bearings of known kind asshown, thebearings for each roll having two sets of somewhat barrel-shaped rollers28 having axially curved bearing faces and which run in oppositelyinclined raceways by which the rollers are held against axial movement,these raceways being formedin. an annular band v2I sleeved and securedon the axle, betweena shoulder on the axle and an end plate 22 securedto the end of the axle. Each backing roll consists essentially of aheavy ring 2|! having an inner bearing face for the bearing rollersformed on an annular band "set in the ring and secured by end members 32and 23. The bearins face of band 2| is spherically curved about on theaxis of rotation of the roll in the middle plane of the roll, and theraoeways in the band 21 are inclined so that the curved bearing faces ofthe bearing rollers bear uniformly against the face of band II. The rollis thus held by its roller bearings against axial movement bodily,

- but is free to tilt on the bearing'rollers about the center ofcurvature of the hearing face of band SI 50 that in the event of anydeflection of its working roll or of its own axle it will. neverthelessthe rim of its working roll.

The blocks 2| and 22 from which the axles for the backing rolls extendare fitted within-the window of the housing so as to be verticallyadjustable therein, being held against movement longitudinally of theaxles by plates l secured to the sides of the housing by bolts 4|extending through the housing, the plates extending inward over theedges of the blocks. The blocks I 1 and I. in which the die roll shaftsl and II arejournaled are fitted to -be vertically slidable within thewindow of the housing, and these blocks'are adjustable horizontallyaxially of the shafts by means of set screws 42 carried by the inwardlyextending portionsof plates 43 which are secured v to the sides of thehousing through the housing.

The roll shafts l5 and it are rotatably mounted and held against endwisemovement within their blocks H and I8. most desirably by sphericalroller bearings 50 similar "0 the bearings for the backing rolls, therebeing two of these bearings for each shaft spaced apart as far aspossible. The inner raceway of each bearing unit is held against ashoulder on the shaft by means of a holding ring 5| screwed on theshaft, and the outer raceway of each bearing unit is held between ashoulder of'the block and a clamping ring 52. These spherical bearings50 not only hold the shafts against endwise movement, but they also takecare of any horizontal fiexure of by bolts 44 extending a center theshafts resulting from tangential forces on the die rolls, all binding atthe bearings due to such fiexure of the shafts being avoided. Each ofthe die rolls is keyed on one of the shaft ends and clamped between ashoulder of the shaft and a clamping nut 53. On one side of the rollstand, th die roll shafts l5 and it are extended to be connected bymeans of suitable coupling units to driving shafts by which'the rollsare rotated in opposite directions at uniform speed.

The vertical dimensions of the blocks l1, l8, 2|

' 'and 22 are such that theseblocks do not come by which a worm wheelinto bearing contact with each other when the rolls are set up incontact. The blocks and rolls are adjusted vertically and subjected topreloading pressure by means of a pair of bottom wedges G0 and a pair oftop wedges 6|. Each bottom wedge 6|! lies between a lower wedge block 62set on the frame and an upper wedge block 63 set in the bottom of theblock 22, and is moved horizontally by a screw it to raise the block 22and by a screw 65 to lower the block. Each of the upper wedges 6| liesbetween an upper wedge block t6 set in the frame and a lower wedge block61 set in the top of the block 2|, and is moved to force the blockdownward bya screw 68 and by a screw 69 to permit the block to beraised. The preloading pressure maybe applied to the rolls by either theupper or the upper wedges, and any suitable means may be provided foroperatingthe wedge screws to apply the necessary pressure to the wedges.As shown, each of the upper screws 68 is turned by means of a hand wheel10 on a worm shaft 1! 12 splined on the screw 68 is turned. A boltthrough the top of the frame and adjustably held by a nut 14 and havingits lower end screwed into th block 2| serves to support this block inposition when the lower block is lowered or any of the rolls removed. Abolt 15 is also provided which extends vertically through the bottompart of the frame and through a nut 16 set in the frame and which bearsat its upp r end against the bottom of block 22 to hold this block up iffor any purpose its wedges are moved out of holding position or removedfrom the mill.

Foreach pair of die rolls, a tubular guide 11 is mounted on the framefor guidingthe tubular blanks or other workpieces to the pass betweenthe die rolls. Each guide is carried by a short bracket extending from aseated in the vertical recess in the side of the frame and verticallyadjustable by screws 1! and securedby cap screws extending throughvertical slots in the plate.

In order that the housing or frame Ill shall have the required strengthand rigidity with a minimum of weight and bulk, the sides, top andbottomof the frame are made of T shape inthe frame. The flanges of thesides of the frame thus extend across the lines of travel oftheworkpieces advancing to and from the two pairs of die rolls. Therefore,the flanges on each side of the frame have openings 8| therein inline'with the pass between the die rolls for the passage therethrough ofthe workpieces, as shown on one side of the frame inFig. 1.

lower wedges, preferably II extending vertically plate I8 removably Insetting up the rolls, the ,die'ijoll blocks are adjusted axiallyof theshafts by 'means'of the screws 42 to bring the die groovesof one'pair ofthe die rolls into vertical alignment. To align the otherpair of dierolls, it is necessary to adlower backing rolls, the upper backing rollsare forced down by-means of .the wedges 6| to press the upper backingrolls against the die rolls and the die rolls of the two pairs together,against the resistance of the lower backing-rolls. The preloadingpressure thus applied to the rolls should be sufficient to take up allclearances andharmful yields in the rolls and their mountings, and, asstated, is most desirably approximately equal to the pressure on therolls in the operation of reducing a tubular blank or other workpiece.The wedges 60 and 6i and their operating screws 64 and 68 thus serve notonly as adjusting means for positioning the .die rolls vertically butalso as preloading means.

If the roll stand is to be used in a single mill, having, therefore,only one pair of working rolls, it' is not necessary accurately to alignthe coacting rolls of the pair on the other end of the die roll shafts.J

' The die rolls, whether the roll stand'is fitted with two pairs of dierolls or with one pair of die rolls and a pair of stress-balancingcoacting rolls ofthe same diameter, are easily accessible for removaland replacement,.-and may be replacedby others of the same diameter orall of adifferent diameter within a limited range. Change in roll sizerequires no other change excepting proper adjustment of the bearingblocks by means of the wedges 80 and GI, and possibly the substitutionof wedges or wedge blocks of different thickness.

Also, rolls grooved for reducing different size tubular blanks and forreducing blanks to different final diameters may, obviously, be used.Whether the rolls of. both pairs carried by the shafts l5 and ii areworking rolls, thatis rolls which apply working pressure to a tube or.other workpiece, or the rolls of one pair are merely stress-balancingrolls, the rolls of both pairs are coacting rolls.

What is claimed is:

1. A duplex roll "stand, comprising a housing, two pairs of overhungworking rolls mounted at opposite sides of the housing fast on twodriven shafts joumalied within the housing, and an overhung backing rollfor each of said working mils. a

.2. A duplex roll stand, comprising a housing,

two pairs of overhung working rolls mounted at opposite sides of thehousing fast on two driven shafts journalled within the housing, and anoverhung backing roll for eachv of said working rolls, said backingrolls being mounted to rotate on fixed axles extending from within thehousing.

3. A duplex roll stand, comprising a housing having a window therein,two pairs of overhung working rolls mounted at opposite sides of thehousing fast on two drivenshafts journalled in blocks verticallyslidable in said window, and an overhung backing roll for each of saidworking rolls, said backing rolls being mounted to rotate on fixed axlesextending from blocks vertically adjustable in said window.

4. A duplex roll stand, comprising a housing having awindow therein, twopairs of overhung working rolls mounted at opposite sides of the housingfast on two driven shafts journalled in blocks vertically slidable insaid window, an overhung backing roll for each of said working rolls,the backing rolls for the upper working rolls being mounted to rotate onfixed axles extending from and integral with a block verticallyadjustable in said window and the backing rolls for the lower workingrolls being mounted to rotate opposite'sides of the housing fast on twodriven shafts journalled within the housing, and an overhung backingroli'for each of said working rolls, each backing-roll being mounted torotate on a' fixed axle extending from within the housing and each beingmounted on its axle by means of 'a spherical bearing permitting thebacking roll to adjust itself to bear evenly on its working roll. Y

6. In a rolling mill, the combination with an overhung working'roll, ofan overhung backing roll mounted to rotate on a fixed axle by means of aspherical bearing permitting the backing roll to adjust itself to bearevenly on the working roll.

7. In a rolling mill, the combination with a working roll, of a backingroll mounted to rotate on a fixed axl'e by means of a spherical bearingpermitting the backing roll to adjust itself to bear evenly on theworking roll;

' 8. A duplex roll stand, comprising a housing housing, the two upperworking rolls being fast on a' shaft 'journalled in a, block verticallyslidable in said window and the two lower working rolls being fast on ashaft journalled in'a block vertically slidable in saidwindow, means foradjusting one of said" blocks axially of its shaft,

overhung backing rolls for the upper working rolls carried by a blockvertically adjustable in said window, and overhung backing rolls for thelower working rolls carried by a block mounted in said window.

J 9. A duplex roll stand, comprising a housing having a window therein,two pairs of overhung working rolls mounted at opposite sides of thehousing, the two upper working rolls being fast on a shaft journalled ina block vertically slidable in said window and the two lower workingrolls being fast on a shaft journalled in a block vertically slidable insaid window, means for adjusting each of said blocks axially of itsshaft, means for adjusting one of said rolls axially on its shaft,overhung backing rolls for the upper .working rolls carried by a blockvertically adhaving a window therein, two pairs of overhung workingrolls mounted at opp site sides of the housing fast on two shaftsjournalled in-blocks slidable in said window, overhung backing rolls forthe upper working rolls carried by a block slidable in said window,overhung backing rolls for the lower working rolls carried by a blockslidable in said window, and means for applying preloading pressure toone of the backing roll blocks to force the backing rolls against theworking rolls and the die rolls of each pair against each other.

11. A duplex roll stand, comprising a housing, two pairs of overhungworking rollsmounted at opposite sides of the housing, an overhungbacking roll for each of said working rolls, and means for applyingpreloading pressure to force the backing rolls against the working rollsand the working rolls of each pair against each other.

12. A duplex roll stand, comprising a cast rectangular frame having awindow therein, two pairs of overhung working rolls mounted at oppositesides of the frame fast on two driven shafts journalled in blocksvertically slidable in said window, and an overhung backing roll foreach of said working rolls, said backing rolls being carried by blocksmounted in said window; one of which last mentioned blocks isvertically,

adjustable, said frame having on each side outer laterally extendingmassive flanges of such width that the over-all width. of the frame atsaid flanges is approximately equal to the distance from the outer sideof the working rolls on one side of the frame to the outer side of theworking rolls on the other side of the frame.

13. A roll stand, oomprisinga housing having a window therein, a pair ofoverhung working rolls on one side of the housing, a pair of overhungcoacting rolls on the other side of the housing, the upper rolls of saidpairs being fast on a shaft journalled in a blockvertically slidable insaid window and the lower rolls of said pairs being fast on a shaftjournalled in a block vertically slidable in said window, means foradjusting one of said blocks axially of its shaft, overhung backingrolls for the upper rolls of said pairs carried by a block mounted insaid window, and overhung backing rolls for the lower rolls of saidpairs carried by a block mounted in said window, one of said backingroll blocks being vertically adjustable.

14. A roll stand, comprising a housing having a window therein, a pairof overhung working rolls on one side of the housing, a pair of overhungcoacting rolls on the other side of thehousing, the upper rolls of saidpairs being fast one. shaft journalled-in a block slidable in saidwindow and the lower rolls of said pairs being fast on a shaftjournalled in a block slidable in said window, overhung backing rollsfor the upper rolls of said pairs carried by a block slidable in saidwindow, overhung backing rolls for the lower rolls of said pairs carriedby a block slidable in said window, and means for applying preloadingpressure to one of the backing roll blocks to force the backing rollsagainst the rolls of each pair and the rolls of said pairs against eachother.

15. A roll stand, comprising a housing having a window therein, a pairof overhung working rolls on one side of the housing, a pair of overhungcoacting rolls on the other side of the housing, the upper rolls of saidpairs being fast on a shaft journalled in a block slidable in saidwindow and the lower rolls of said pairs being fast on a shaftjournalled in a block slidable in said window, overhung backing rollsfor the upper rolls of said pairs carriedby a block slidable in saidwindow, backing rolls for the lower rolls of said pairs, and means forapplying preloading pressure to'cthe blockwhich carries the upperbacking rolls to force the-backing rolls against the rolls ofsaidpairs'and the rolls of each pair against each other.

116. A roll stand, comprising a housing having a window therein, a pairof overhung working rolls on one side of the housing, a pair of overhungcoacting rolls on the other side of the housing, an overhung backingroll for each of the rolls of said pairs, and means for applyingpreloading pressure to force the backing rolls against the rolls of saidpairs and the rolls of each pair against each other.

17. A roll stand, comprisinga cast rectangular frame having a windowtherein, a pair of overhung working rolls on one side of the frame, a

pair of overhung coacting rolls on the other side of the frame, therollsof said pairs being fast on two driven shafts journalled in blocksslidable in said window, and an overhung backing roll for each roll ofeach of said pairs, said backing rolls being carried by blocksadjustable in said window, said frame having on each side outerlaterally extending massive fianges of such width that the over-allwidth of the frame at said flanges is approximately equal to thedistance from the outer side of the rolls of the pair on one side of theframe to the outer side of the rolls of the pair on the other side ofthe frame.

. HEBER C. INSLEE.

